Its all about the Cellular Communications.

1. Cellular Communication
1

2. History
• Radio communication was invented by Marconi, in 1893.
• In 1940, the first walkie-talkie was used by the US military.
• In 1947, John Bardeen and Walter Brattain from AT&T’s Bell Labs invented the transistor.
• In 1979 the first commercial cellular phone service was launched by the Nordic Mobile Telephone
(in Finland, Sweden, Norway, Denmark).
2

3. Cellular systems generations
• 1G (first generation) – voice-oriented systems based on analog technology; ex.:
Advanced Mobile Phone Systems (AMPS)
• 2G (second generation) - voice-oriented systems based on digital technology; more
efficient and used less spectrum than 1G;
ex.: Global System for Mobile (GSM) and US Time Division Multiple
Access (US- TDMA)
• 3G (third generation) – high-speed voice-oriented systems integrated with data
services;
ex.: General Packet Radio Service (GPRS), Code Division Multiple Access
(CDMA)
• 4G (fourth generation) – mobile ultra-broadband Internet access, for example to
laptops with USB, wireless modems to smart phones and to other mobile devices.
3

4. Network Cells
4
CELL:
Its a geographical unit of a
cellular network; is the area
around an antenna where a
specific frequency range is used;
is represented graphically as a
hexagonal shape, but in reality it
is irregular in shape.

5. Types of cells
5
• Macrocell – their coverage is large (aprox. 6 miles in
diameter); used in remote areas, high-power transmitters
and receivers are used.
• Microcell – their coverage is small (half a mile in
diameter) and are used in urban zones; low-powered
transmitters and receivers are used to avoid interference
with cells in another clusters.
• Picocell – covers areas such as building or a tunnel.

6. Components of a cellular phone
• Radio transceiver – low power radio and receiver.
• transmitter
• Antenna - which is usually located inside the phone.
• Control circuitry – formats the data sent to and from the BTS; controls
signal transmission and reception.
• Man-machine interface – consists from a keypad and a display; is
managed by the control circuitry.
• SIM – integrated circuit card that stores the identity information of
subscriber.
• Battery- usually Li-ion, the power unit of the phone.
6

7. Cellular network components
7
• BTS (Base Transceiver Station) – main component of a cell and it connects the
subscribers to the cellular network; for transmission/reception of information it uses several
antennas spread across the cell.
• BSC (Basic Station Controller) – it is an interface between BTSs and it is linked to BTSs
by cable or microwave links; it routes calls between BTSs; it is also connected to the MSC.
• MSC (Mobile Switching Center) – the coordinator of a cellular network, it is connected to
several BSCs, it routes calls between BSCs; links the cellular network with other networks like
PSTN through fiber optics, microwave or copper cable.

8. Making a call process
8
• The subscriber dials the receiver’s number and sends it to the BTS
• The BTS sends to its BSC; the ID, location and number of the caller and also the
number of the receiver.
• The BSC forwards this information to its MSC.
• The MSC routes the call to the receiver’s MSC which is then sent to the
receiver’s BSC and then to its BTS.
• The communication with the receiver’s cell phone is established.

9. Receiving a call process
9
• When the receiver’s phone is in an idle state it listens for the control
channel of its BTS.
• If there is an incoming call the BSC and BTS sends a message to
the cells in the area where the receiver’s phone is located.
• The phone monitors its message and compares the number from the
message with its own.
• If the numbers matches the cell phone sends an acknowledgement to
the BTS.
after authentication, the communication is established between the
caller and
the receiver.

10. Roaming
10
• Allowing the subscriber to send/receive calls outside the service provider’s
coverage area.

11. Cellular services
• Voice communication.
• Short Messaging Service
(SMS) .
• Multimedia Messaging
Service (MMS) .
• Global Positioning
System (GPS).
• Wireless Application Protocol (WAP) – to
access the Internet.
• Security (PIN). 11

12. Conclusion
• The development of Cellular Communication is the first step towards a true personal
communication system that will allow communication anywhere, anytime, and with
anyone.
12

13. Thank You
13